Selective locking apparatus



March 10, 1931. c, BEALL 1,795,420

SELECTIVE LOCKING APPARATUS Filed April 24, 1928 INVENTOR 2 ga/efimu;

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Patented Mar. 10, 1931 hairs ana tries f- CHARLES R. BEALLQOF nnenwoon BOROUGH, PENNSYLVANIA,ASSIGNOR TO THE UNION swrroira s enaeoomran' or swissvaitn, PENNSYLVANIA,- A con-3o- Barronv or rnnnsrtva'n'ia S LECTIV LOCKING arrnnarus f i v Application filed A ril 24,

My'invention relat'er to selectivedocking apparatus, and particularly to apparatus of the type involving a device moved between two extreme positions by a plurality of rotations ofa shaft. One object of my invention is the provision of means for-locking such device 1 in either extreme: position by locking the shaft whiohmoves it, butfor pref venting the shaft frombeing lockediwhen the' 'device is in any intermediate position.

will'deseribe several forms of apparatus embodyingfmy invention; and will then'point out the novel features thereof'in claims;

In the accom an in drawin Fi l'is a P m). a

- view showing one form, of'apparatus embodying my invention. Fig. 2 is'a top view of the apparatus" shown in Fig. 1. Figs. 3

ands are views showing modified forms of the anparatus illustrated "III'FIgS. 1 and 2,

" and also embodying my invention;

Similar reference characters refer' to sim; ilar parts in each of the several. views I fReferringfirst toFigs'. 1 andQ, the reference characteel designates a portion of a rotatable shaft which operates a device leetween two extremepositions. As here shown, the device is a nut B threaded upon the shaft so that 'by rotation of the shaft the nut-m'ay be moved from the positio'nin which it is illustrated in full lines in the drawing to the position indicated by the dotted'flines at B The nut B maybe connected'with other apparatus not shownin the drawing, such for example, as an electric oil switch or a discon-. necting switch having extreme positions'c'on esponding to the extreme positions of nut Bl vIn apparatus ofth'eitype suggested it is desirable to lock the'nutin either extreme position to prevent accidental or malicious displacement of the apparatus connected therewith. I prefer to accomplish this result by locking the shaft 1 which drives the nut B. For this purpose I attach to the shaft 1 a pinion 2 and a circular locking plate 3. Meshing with the pinion'2 is a gear wheel 5 which is journalled on the shaft 4, and to which is attached a second circular locking plate 6. It follows, therefore, that when shaft 1 is rotated, the locking plates 3 and 6 are both rotated, but as here shown these two in anyv two positions. t

1e2s.' Serial nojevaass.

plates rotate in opposite directionsand turn. through different angles for a givenangular The supply of currentto magnet A may be controlled by any suitable means not shown iirthe'd'rawing; y a

The locking plate 3 is providedat its periphery with a notch 10, and the locking plate 6 is provided with'two. spaced notches ll and 12. f The various parts are so proportioned and disposed that when Qtlie'nut B is in one extreme position; in which'it is illustrated in the drawing, notch 10' in ,plate 3 and-notch 11 in .plate6 are in alignn'lent If magnet A is then 'de-energized,;spring 8 urges the plunger into notches 1'0 and 11 to lock the platesfand hencethe shaft 1 and the nut B, in the positions Wl1lCll' l3l16S parts then 00- cupy." The apparatus may be unlocked by energizing magnet A to withdraw plunger .7 from notches 10 and 1-1. The'shaftanay then be rotated to movethe'nut'B to its other extreme position ywhereupon notch 10 in plate. 3 notchl l2 1in plate o become aligned, .andr fjthe magnet A isjthe r i energized, the :p t

tween'rpinion2 and gear wl1eel"5.--and the locations of the-locking notches,-the a, pa'ratus may be-designed to lock the nut B In the modified forin ofaapparatus shown in Fig. 3, the shaft 1 carries two gear wheels.

B'y properly choosing the gear ratio he- 7 2 and119f, ofdiflerent: sizes,.whichdrive-twoV othergea1i'wheels and '18,. res pectively. Gear wheels'5 and IS-are-journalledon the fixed shaft 4:. Attached to gear wheel 5 is a circular locking plate 13 which is provided at its periphery with a notch 16. A similar locking plate 24 is attached to the gear wheel 18 and is provided with a notch 17.

The parts are so proportioned that when the not driven by shaft 1 occupies one extreme position, the locking plunger 7 enters notches 16 and 17 to lock the parts in position. If the plunger is withdrawn and the shaft 1 rotated, the locking plates will rotate at different speeds until the plates 13 and 24 again occupy positions in which notches 16 and 17 receive plunger 7 The gear ratios of gear wheels 2 and 5 and of gear wheels 19 and 18, and the dimensions of the plates 13 and 24 are so chosen that this second looking position corresponds to the other extreme position of the nut B. It will be seen that for all positions of the nut between its two extreme positions, the plunger rides on the periphery of at least one of the locking plates so that the parts can be locked only when nut B occupies an extreme position.

Referring now to Fig. 4, the shaft 1 carries a broad faced pinion 20, which is rigidly attached to the shaft. The pinion 2O meshes with a gear wheel 25, which is attached to a locking drum 21 provided with spaced holes 22 and 23 and threaded on a fixed spindle 26. When shaft 1 is rotated, pinion 2O drives gear wheel 25, which travels upwardly or downwardly on the spindle 26 depending upon the direction of rotation of the shaft. When the nut B, driven by shaft 1, occupies either extreme position, one of the holes 22 or 23 in drum 21 is opposite plunger 17 so that if magnet A is de-energized the plunger enters the hole to lock the parts in position. l/Vhen the nut is in an intermediate position, however, the plunger bears against the surface of the drum 21 and can not lock the parts.

It will be clear from the foregoing that I have devised several forms of apparatus for locking in either of two extreme positions a device driven by a shaft which performs a plurality of rotations in moving the device between such positions. Furthermore, the apparatus is ineffective to lock the parts when the device occupies any intermediate position.

Although I have herein shown and described only a few forms of selective locking apparatus embodying my invention, it is understood that various changes and modifications may be made therein Within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, a rotatable shaft, two circular locking plates, means for rotating the plates at different angular velocities in response to rotation of the shaft, and means for locking the plates when and only when they have either of two predetermined relative positions.

2. In combination, a rotatable shaft, a device movable between two extreme positions by a plurality of rotations of said shaft, a locking plate driven by said shaft, means for locking said plate when said device occupies either of said extreme positions, and means driven by said shaft for rendering said look ing means ineffective when the device occupies any intermediate position.

3. In combination, a rotatable shaft, a device movable between two extreme positions by a plurality of rotations of said shaft, two circular locking plates driven by said shaft and arranged to turn through different angles for a given angular movement of said shaft, a locking plunger bearing against the edges of both said plates, and notches in said plates to receive said plunger and lock the plates when and only when said device occupies one of its extreme positions.

4:. Selective locking apparatus comprising a rotatable shaft, two circular locking plates each provided at its periphery with a notch, means for rotating said plates at different rates in response to rotation of said shaft,

and a locking plunger for entering said notches when both notches are aligned with said plunger simultaneously.

5. In combination, a rotatable shaft, a device movable between two extreme positions by a plurality of rotations of said shaft, a

first locking plate attached to said shaft, a second locking plate geared to said shaft, and means for locking both said plates when and only when said device occupies either of said extreme positions.

6. In combination, a rotatable shaft, a device movable between two extreme positions by a plurality of rotations of said shaft, a first and a second gear wheels rigidly attached to said shaft, two other gear wheels meshing with said first and second gear wheels, respectively, two locking plates one driven by each of said two other gear wheels, and means for locking said locking plates when and only when said device occupies either of its extreme positions.

In testimony whereof I aiiix my signature.

CHARLES R. BEALL. 

